SECTION TILT-UP PRECAST CONCRETE SANDWICH PANELS. A. Work includes, but is not limited to, the following:

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1 PART 1 GENERAL 1.01 SUMMARY SECTION TILT-UP PRECAST CONCRETE SANDWICH PANELS A. Work includes, but is not limited to, the following: 1. Architectural precast concrete sandwich wall panels. 2. Integral insulation. 3. Forms, form liner, and casting beds. 4. Reinforcing steel, accessories, and connecting rods. 5. Lifting inserts. 6. Brace inserts. 7. Erection and bracing. B. Comply with requirements of Section Tilt-Up Precast Concrete. C. Items installed under this section but specified elsewhere, include, but are not limited to, embedded plates and anchors for connection to other materials. D. Related Sections: Concrete Testing Cast-In-Place Concrete Tilt-Up Precast Concrete Joint Sealants Steel Doors and Frames REFERENCES A. American Society for Testing and Materials (ASTM): 1. A Specification for Steel Welded Wire Fabric, Plain, for Concrete Reinforcement. 2. A615/A-96a Specification for Deformed and Plain Billet-Steel Bars for Concrete Reinforcement. 3. C Specification for Rigid, Cellular Polystyrene Thermal Insulation SUBMITTALS A. Concrete Mix Designs: For each mix variation specified. Project No. SPECIFICATION GUIDELINES

2 B. Shop Drawings: 1. Reinforcing steel. 2. Layout drawings showing placement of embedded plates, anchors, pins, insulation, lifting inserts, and brace inserts. 3. Rigging arrangement, cable lengths, bracing arrangement, and panel weights. C. Design calculations by a Florida registered professional engineer. D. Manufacturer's Literature: Insulation descriptive data. PART 2 PRODUCTS 2.01 CONCRETE REQUIREMENTS A. Structural Panel: 1. Compressive Strength: 3,000 psi at 28 days. 2. Slump: 4 inches + 1 inch. 3. Air Content: 5 percent + 1 percent. B. Facing: 1. Compressive Strength: 3,000 psi at 28 days. 2. Slump: 4 inches + 1 inch. 3. Air Content: 5 percent + 1 percent. 4. Cement: Single source supplier MATERIALS A. Concrete Materials: Refer to Section Cast-In-Place Concrete. B. Reinforcing: 1. Structural Panel: Deformed billet steel complying with ASTM A615, Grade Facing: a. Welded wire fabric complying with ASTM A185. b. Provide in flat sheets. Project No. SPECIFICATION GUIDELINES

3 C. Insulation: c. Chairs: Plastic only. 1. Extruded polystyrene complying with ASTM C578, Type IV. 2. Thickness: 2 inches. 3. R Value: Compressive Strength: 25 psi. 5. Provide with 7/16" diameter holes at 16 inches on center each way. 6. Flame Spread Ratings: a. 75 or less for 1-story buildings. b. 25 or less for 2 or more stories. 7. Smoke Development Rating: 450 or less. 8. Products: a. Styrofoam by Dow Chemical Co. b. Accepted equivalent. D. Connecting Rods: 1. Material: a. Fibers in chemically resistant thermal set polymer. b. Permeance Seal: 1) Molded collar of high impact, alkaline resistant polymer. 2) Molded to connecting rod and positioned for specific wall configuration. 2. Tensile and Flexural Strength: 120,000 psi minimum. 3. Coefficient of Elasticity: in/in/degrees F. 4. Thermal Conductivity: 2.1 Btu/sf/hr/degrees F/in. 5. Effective Cross Section: 3/16 square inch. 6. Products: a. Thermomass-PC by Composite Technologies Corp. b. Accepted equivalent. E. Sealant: As specified in Section Joint Sealers. F. Grout: Dry pack sand/cement, minimum strength, 4,000 psi at 28 days. Project No. SPECIFICATION GUIDELINES

4 G. Bond Breaker: Compatible with coating, adhesive, or sealant applied to panel surfaces. H. Lifting and Bracing Inserts: Size and type required for each panel shall be as shown on approved shop drawings. PART 3 EXECUTION 3.01 PREPARATION A. Casting Surfaces: Provide level, steel troweled casting surfaces. B. Sweep clean. C. Bond Breaker: 1. Apply minimum of 2 coats of bond breaker material according to manufacturer's published instructions. Provide second coat at 90 degrees to first. 2. Inspect each panel to insure adequate coverage. 3. Do not apply bond breaker material after placement of reinforcing bars EMBEDDED ITEMS A. Place embedded plates, anchors, and inserts accurately according to approved layout shop drawings. B. Verify locations for embedded door anchors and coordinate blockouts for future doorframe grouting or place concrete with doorframe in place. C. Tie securely to prevent dislocation during placing of concrete. D. Do not weld embedded items to reinforcing unless additional reinforcing is provided specifically for this purpose. E. Do not weld lifting inserts. F. Notify A/E if embedded items are cast into panel in wrong locations. G. Do not field modify connections without specific Project No. SPECIFICATION GUIDELINES

5 instructions or approval of A/E PANEL FABRICATION A. Install lower wythe structural temperature reinforcing and lifting hardware. B. Pour lower wythe of concrete over reinforcing and hardware. Screed to desired level. C. Insulation: 1. Lay insulation over concrete while concrete is still plastic. 2. Fit tightly to edge of forms and block-outs. D. Connecting Rods: 1. Insert into holes of insulation until flange is fully seated against insulation. 2. Consolidate by applying foot pressure on insulation board in vicinity of connecting rod shortly after insertion. 3. Verify consolidation by removing (then replacing) 3 or 4 connecting rods per 500 square feet of panel. E. Install second layer of structural or temperature reinforcing or lifting hardware. F. Pour second layer of concrete and screed to desired level. G. Finish: Finish top face as specified for Trowel Finish in Section 03300, Cast-In-Place Concrete. H. Tolerances: Fabrication tolerances are as follows: 1. Length and Height: a. Up to 10 feet: + 1/8", - 3/8". b. 10 feet to 20 feet: + 1/8", - 1/2". c. Over 20 feet: + 1/8", - 3/8". 2. Thickness: Overall + 3/16". 3. Straightness (deviation from intended line: a. Up to 10 feet: 3/8". b. 10 feet to 20 feet: + 5/8". Project Name M-DCPS MASTER July 01 Project No. SPECIFICATION GUIDELINES

6 c. 20 feet to 40 feet: + 3/4". 4. Skewness (measured as tolerance in length of diagonal: 3.04 ERECTION a. Up to 10 feet: + 3/8". b. 10 feet to 20 feet: + 5/8". c. 20 feet to 40 feet: + 3/4". A. Do not erect panels until concrete is 14 days old unless concrete strength has been verified by cylinder testing to be 3,000 psi minimum. B. Use spreader beams and cable rigging as shown on approved shop drawings. C. Minimum cable lengths as indicated. D. Inspect inserts at start of lift to insure connections are holding properly. E. Coordinate panel erection sequence and follow special lifting sequences as may be required. F. Continue with lift as continuous process until panel is vertical. G. Avoid intermediate stops. H. Lower panels into position on shims or grout pads. I. Install bracing securely before removal of rigging. Maintain bracing and supports in place and undisturbed until closures, columns, or other supporting structures have been installed and are capable of receiving panels. J. Erect panels without damage to shape or finish. K. Replace or repair damaged panels. L. Erect members level and plumb within acceptable tolerances. M. Align and maintain uniform horizontal and vertical joints as erection progresses STRUCTURAL GROUTING Project Name M-DCPS MASTER July 01 Project No. SPECIFICATION GUIDELINES

7 A. Install grout under concrete panels. B. Dry Pack Sand Cement: 1. Mix: One part Portland cement, 2-1/2 parts sand that will pass No.16 screen, and sufficient water to produce grout that will stick together, but not exude water and not rubbery or crumbly. 2. Begin dry pack placement and compaction against solid backing. 3. In lieu of dry pack material, flowable factory mixed nonshrink grout may be used. 4. Do not use truck mixed grout. C. Placement: 1. Place grout as soon as possible after concrete panels have been plumbed and secured in position. 2. Clean space of water and debris before placing grout. 3. Pack fully under panels SURFACE TREATMENT A. Exterior face of panels to receive Smooth Form Finish as specified in section Cast-In-Place Concrete. B. Rubbed Finish of interior or exterior faces of panels is not required. C. Patch and rub holes made by lifting inserts where visible after finishes have been installed. END OF SECTION Project Name M-DCPS MASTER July 01 Project No. SPECIFICATION GUIDELINES